![Ross Zwisler](/assets/img/avatar_default.png)
Add locking to ensure that DAX faults are isolated from ext2 operations that modify the data blocks allocation for an inode. This is intended to be analogous to the work being done in XFS by Dave Chinner: http://www.spinics.net/lists/linux-fsdevel/msg90260.html Compared with XFS the ext2 case is greatly simplified by the fact that ext2 already allocates and zeros new blocks before they are returned as part of ext2_get_block(), so DAX doesn't need to worry about getting unmapped or unwritten buffer heads. This means that the only work we need to do in ext2 is to isolate the DAX faults from inode block allocation changes. I believe this just means that we need to isolate the DAX faults from truncate operations. The newly introduced dax_sem is intended to replicate the protection offered by i_mmaplock in XFS. In addition to truncate the i_mmaplock also protects XFS operations like hole punching, fallocate down, extent manipulation IOCTLS like xfs_ioc_space() and extent swapping. Truncate is the only one of these operations supported by ext2. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.com>
832 lines
28 KiB
C
832 lines
28 KiB
C
/*
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* Copyright (C) 1992, 1993, 1994, 1995
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* Remy Card (card@masi.ibp.fr)
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* Laboratoire MASI - Institut Blaise Pascal
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* Universite Pierre et Marie Curie (Paris VI)
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*
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* from
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*
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* linux/include/linux/minix_fs.h
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*/
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#include <linux/fs.h>
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#include <linux/ext2_fs.h>
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#include <linux/blockgroup_lock.h>
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#include <linux/percpu_counter.h>
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#include <linux/rbtree.h>
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/* XXX Here for now... not interested in restructing headers JUST now */
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/* data type for block offset of block group */
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typedef int ext2_grpblk_t;
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/* data type for filesystem-wide blocks number */
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typedef unsigned long ext2_fsblk_t;
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#define E2FSBLK "%lu"
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struct ext2_reserve_window {
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ext2_fsblk_t _rsv_start; /* First byte reserved */
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ext2_fsblk_t _rsv_end; /* Last byte reserved or 0 */
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};
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struct ext2_reserve_window_node {
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struct rb_node rsv_node;
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__u32 rsv_goal_size;
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__u32 rsv_alloc_hit;
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struct ext2_reserve_window rsv_window;
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};
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struct ext2_block_alloc_info {
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/* information about reservation window */
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struct ext2_reserve_window_node rsv_window_node;
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/*
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* was i_next_alloc_block in ext2_inode_info
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* is the logical (file-relative) number of the
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* most-recently-allocated block in this file.
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* We use this for detecting linearly ascending allocation requests.
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*/
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__u32 last_alloc_logical_block;
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/*
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* Was i_next_alloc_goal in ext2_inode_info
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* is the *physical* companion to i_next_alloc_block.
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* it the the physical block number of the block which was most-recentl
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* allocated to this file. This give us the goal (target) for the next
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* allocation when we detect linearly ascending requests.
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*/
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ext2_fsblk_t last_alloc_physical_block;
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};
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#define rsv_start rsv_window._rsv_start
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#define rsv_end rsv_window._rsv_end
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/*
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* second extended-fs super-block data in memory
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*/
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struct ext2_sb_info {
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unsigned long s_frag_size; /* Size of a fragment in bytes */
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unsigned long s_frags_per_block;/* Number of fragments per block */
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unsigned long s_inodes_per_block;/* Number of inodes per block */
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unsigned long s_frags_per_group;/* Number of fragments in a group */
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unsigned long s_blocks_per_group;/* Number of blocks in a group */
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unsigned long s_inodes_per_group;/* Number of inodes in a group */
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unsigned long s_itb_per_group; /* Number of inode table blocks per group */
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unsigned long s_gdb_count; /* Number of group descriptor blocks */
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unsigned long s_desc_per_block; /* Number of group descriptors per block */
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unsigned long s_groups_count; /* Number of groups in the fs */
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unsigned long s_overhead_last; /* Last calculated overhead */
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unsigned long s_blocks_last; /* Last seen block count */
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struct buffer_head * s_sbh; /* Buffer containing the super block */
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struct ext2_super_block * s_es; /* Pointer to the super block in the buffer */
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struct buffer_head ** s_group_desc;
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unsigned long s_mount_opt;
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unsigned long s_sb_block;
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kuid_t s_resuid;
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kgid_t s_resgid;
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unsigned short s_mount_state;
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unsigned short s_pad;
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int s_addr_per_block_bits;
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int s_desc_per_block_bits;
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int s_inode_size;
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int s_first_ino;
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spinlock_t s_next_gen_lock;
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u32 s_next_generation;
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unsigned long s_dir_count;
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u8 *s_debts;
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struct percpu_counter s_freeblocks_counter;
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struct percpu_counter s_freeinodes_counter;
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struct percpu_counter s_dirs_counter;
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struct blockgroup_lock *s_blockgroup_lock;
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/* root of the per fs reservation window tree */
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spinlock_t s_rsv_window_lock;
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struct rb_root s_rsv_window_root;
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struct ext2_reserve_window_node s_rsv_window_head;
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/*
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* s_lock protects against concurrent modifications of s_mount_state,
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* s_blocks_last, s_overhead_last and the content of superblock's
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* buffer pointed to by sbi->s_es.
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*
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* Note: It is used in ext2_show_options() to provide a consistent view
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* of the mount options.
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*/
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spinlock_t s_lock;
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};
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static inline spinlock_t *
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sb_bgl_lock(struct ext2_sb_info *sbi, unsigned int block_group)
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{
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return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);
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}
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/*
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* Define EXT2FS_DEBUG to produce debug messages
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*/
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#undef EXT2FS_DEBUG
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/*
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* Define EXT2_RESERVATION to reserve data blocks for expanding files
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*/
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#define EXT2_DEFAULT_RESERVE_BLOCKS 8
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/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
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#define EXT2_MAX_RESERVE_BLOCKS 1027
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#define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
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/*
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* The second extended file system version
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*/
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#define EXT2FS_DATE "95/08/09"
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#define EXT2FS_VERSION "0.5b"
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/*
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* Debug code
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*/
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#ifdef EXT2FS_DEBUG
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# define ext2_debug(f, a...) { \
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printk ("EXT2-fs DEBUG (%s, %d): %s:", \
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__FILE__, __LINE__, __func__); \
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printk (f, ## a); \
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}
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#else
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# define ext2_debug(f, a...) /**/
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#endif
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/*
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* Special inode numbers
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*/
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#define EXT2_BAD_INO 1 /* Bad blocks inode */
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#define EXT2_ROOT_INO 2 /* Root inode */
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#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
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#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
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/* First non-reserved inode for old ext2 filesystems */
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#define EXT2_GOOD_OLD_FIRST_INO 11
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static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
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{
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return sb->s_fs_info;
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}
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/*
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* Macro-instructions used to manage several block sizes
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*/
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#define EXT2_MIN_BLOCK_SIZE 1024
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#define EXT2_MAX_BLOCK_SIZE 4096
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#define EXT2_MIN_BLOCK_LOG_SIZE 10
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#define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
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#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
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#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
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#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
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#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
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#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
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/*
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* Macro-instructions used to manage fragments
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*/
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#define EXT2_MIN_FRAG_SIZE 1024
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#define EXT2_MAX_FRAG_SIZE 4096
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#define EXT2_MIN_FRAG_LOG_SIZE 10
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#define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
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#define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
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/*
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* Structure of a blocks group descriptor
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*/
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struct ext2_group_desc
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{
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__le32 bg_block_bitmap; /* Blocks bitmap block */
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__le32 bg_inode_bitmap; /* Inodes bitmap block */
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__le32 bg_inode_table; /* Inodes table block */
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__le16 bg_free_blocks_count; /* Free blocks count */
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__le16 bg_free_inodes_count; /* Free inodes count */
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__le16 bg_used_dirs_count; /* Directories count */
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__le16 bg_pad;
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__le32 bg_reserved[3];
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};
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/*
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* Macro-instructions used to manage group descriptors
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*/
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#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
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#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
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#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
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#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
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/*
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* Constants relative to the data blocks
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*/
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#define EXT2_NDIR_BLOCKS 12
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#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
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#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
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#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
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#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
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/*
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* Inode flags (GETFLAGS/SETFLAGS)
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*/
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#define EXT2_SECRM_FL FS_SECRM_FL /* Secure deletion */
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#define EXT2_UNRM_FL FS_UNRM_FL /* Undelete */
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#define EXT2_COMPR_FL FS_COMPR_FL /* Compress file */
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#define EXT2_SYNC_FL FS_SYNC_FL /* Synchronous updates */
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#define EXT2_IMMUTABLE_FL FS_IMMUTABLE_FL /* Immutable file */
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#define EXT2_APPEND_FL FS_APPEND_FL /* writes to file may only append */
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#define EXT2_NODUMP_FL FS_NODUMP_FL /* do not dump file */
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#define EXT2_NOATIME_FL FS_NOATIME_FL /* do not update atime */
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/* Reserved for compression usage... */
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#define EXT2_DIRTY_FL FS_DIRTY_FL
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#define EXT2_COMPRBLK_FL FS_COMPRBLK_FL /* One or more compressed clusters */
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#define EXT2_NOCOMP_FL FS_NOCOMP_FL /* Don't compress */
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#define EXT2_ECOMPR_FL FS_ECOMPR_FL /* Compression error */
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/* End compression flags --- maybe not all used */
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#define EXT2_BTREE_FL FS_BTREE_FL /* btree format dir */
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#define EXT2_INDEX_FL FS_INDEX_FL /* hash-indexed directory */
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#define EXT2_IMAGIC_FL FS_IMAGIC_FL /* AFS directory */
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#define EXT2_JOURNAL_DATA_FL FS_JOURNAL_DATA_FL /* Reserved for ext3 */
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#define EXT2_NOTAIL_FL FS_NOTAIL_FL /* file tail should not be merged */
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#define EXT2_DIRSYNC_FL FS_DIRSYNC_FL /* dirsync behaviour (directories only) */
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#define EXT2_TOPDIR_FL FS_TOPDIR_FL /* Top of directory hierarchies*/
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#define EXT2_RESERVED_FL FS_RESERVED_FL /* reserved for ext2 lib */
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#define EXT2_FL_USER_VISIBLE FS_FL_USER_VISIBLE /* User visible flags */
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#define EXT2_FL_USER_MODIFIABLE FS_FL_USER_MODIFIABLE /* User modifiable flags */
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/* Flags that should be inherited by new inodes from their parent. */
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#define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\
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EXT2_SYNC_FL | EXT2_NODUMP_FL |\
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EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\
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EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\
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EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)
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/* Flags that are appropriate for regular files (all but dir-specific ones). */
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#define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))
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/* Flags that are appropriate for non-directories/regular files. */
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#define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)
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/* Mask out flags that are inappropriate for the given type of inode. */
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static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
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{
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if (S_ISDIR(mode))
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return flags;
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else if (S_ISREG(mode))
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return flags & EXT2_REG_FLMASK;
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else
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return flags & EXT2_OTHER_FLMASK;
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}
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/*
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* ioctl commands
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*/
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#define EXT2_IOC_GETFLAGS FS_IOC_GETFLAGS
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#define EXT2_IOC_SETFLAGS FS_IOC_SETFLAGS
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#define EXT2_IOC_GETVERSION FS_IOC_GETVERSION
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#define EXT2_IOC_SETVERSION FS_IOC_SETVERSION
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#define EXT2_IOC_GETRSVSZ _IOR('f', 5, long)
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#define EXT2_IOC_SETRSVSZ _IOW('f', 6, long)
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/*
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* ioctl commands in 32 bit emulation
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*/
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#define EXT2_IOC32_GETFLAGS FS_IOC32_GETFLAGS
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#define EXT2_IOC32_SETFLAGS FS_IOC32_SETFLAGS
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#define EXT2_IOC32_GETVERSION FS_IOC32_GETVERSION
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#define EXT2_IOC32_SETVERSION FS_IOC32_SETVERSION
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/*
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* Structure of an inode on the disk
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*/
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struct ext2_inode {
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__le16 i_mode; /* File mode */
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__le16 i_uid; /* Low 16 bits of Owner Uid */
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__le32 i_size; /* Size in bytes */
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__le32 i_atime; /* Access time */
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__le32 i_ctime; /* Creation time */
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__le32 i_mtime; /* Modification time */
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__le32 i_dtime; /* Deletion Time */
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__le16 i_gid; /* Low 16 bits of Group Id */
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__le16 i_links_count; /* Links count */
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__le32 i_blocks; /* Blocks count */
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__le32 i_flags; /* File flags */
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union {
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struct {
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__le32 l_i_reserved1;
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} linux1;
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struct {
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__le32 h_i_translator;
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} hurd1;
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struct {
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__le32 m_i_reserved1;
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} masix1;
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} osd1; /* OS dependent 1 */
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__le32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
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__le32 i_generation; /* File version (for NFS) */
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__le32 i_file_acl; /* File ACL */
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__le32 i_dir_acl; /* Directory ACL */
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__le32 i_faddr; /* Fragment address */
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union {
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struct {
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__u8 l_i_frag; /* Fragment number */
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__u8 l_i_fsize; /* Fragment size */
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__u16 i_pad1;
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__le16 l_i_uid_high; /* these 2 fields */
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__le16 l_i_gid_high; /* were reserved2[0] */
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__u32 l_i_reserved2;
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} linux2;
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struct {
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__u8 h_i_frag; /* Fragment number */
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__u8 h_i_fsize; /* Fragment size */
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__le16 h_i_mode_high;
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__le16 h_i_uid_high;
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__le16 h_i_gid_high;
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__le32 h_i_author;
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} hurd2;
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struct {
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__u8 m_i_frag; /* Fragment number */
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__u8 m_i_fsize; /* Fragment size */
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__u16 m_pad1;
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__u32 m_i_reserved2[2];
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} masix2;
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} osd2; /* OS dependent 2 */
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};
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#define i_size_high i_dir_acl
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#define i_reserved1 osd1.linux1.l_i_reserved1
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#define i_frag osd2.linux2.l_i_frag
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#define i_fsize osd2.linux2.l_i_fsize
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#define i_uid_low i_uid
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#define i_gid_low i_gid
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#define i_uid_high osd2.linux2.l_i_uid_high
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#define i_gid_high osd2.linux2.l_i_gid_high
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#define i_reserved2 osd2.linux2.l_i_reserved2
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/*
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* File system states
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*/
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#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
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#define EXT2_ERROR_FS 0x0002 /* Errors detected */
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/*
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* Mount flags
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*/
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#define EXT2_MOUNT_CHECK 0x000001 /* Do mount-time checks */
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#define EXT2_MOUNT_OLDALLOC 0x000002 /* Don't use the new Orlov allocator */
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#define EXT2_MOUNT_GRPID 0x000004 /* Create files with directory's group */
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#define EXT2_MOUNT_DEBUG 0x000008 /* Some debugging messages */
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#define EXT2_MOUNT_ERRORS_CONT 0x000010 /* Continue on errors */
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#define EXT2_MOUNT_ERRORS_RO 0x000020 /* Remount fs ro on errors */
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#define EXT2_MOUNT_ERRORS_PANIC 0x000040 /* Panic on errors */
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#define EXT2_MOUNT_MINIX_DF 0x000080 /* Mimics the Minix statfs */
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#define EXT2_MOUNT_NOBH 0x000100 /* No buffer_heads */
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#define EXT2_MOUNT_NO_UID32 0x000200 /* Disable 32-bit UIDs */
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#define EXT2_MOUNT_XATTR_USER 0x004000 /* Extended user attributes */
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#define EXT2_MOUNT_POSIX_ACL 0x008000 /* POSIX Access Control Lists */
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#define EXT2_MOUNT_XIP 0x010000 /* Obsolete, use DAX */
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#define EXT2_MOUNT_USRQUOTA 0x020000 /* user quota */
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#define EXT2_MOUNT_GRPQUOTA 0x040000 /* group quota */
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#define EXT2_MOUNT_RESERVATION 0x080000 /* Preallocation */
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#ifdef CONFIG_FS_DAX
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#define EXT2_MOUNT_DAX 0x100000 /* Direct Access */
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#else
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#define EXT2_MOUNT_DAX 0
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#endif
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#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
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#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
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#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
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EXT2_MOUNT_##opt)
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/*
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* Maximal mount counts between two filesystem checks
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*/
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#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
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#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
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/*
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* Behaviour when detecting errors
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*/
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#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
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#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
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#define EXT2_ERRORS_PANIC 3 /* Panic */
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#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
|
|
|
|
/*
|
|
* Structure of the super block
|
|
*/
|
|
struct ext2_super_block {
|
|
__le32 s_inodes_count; /* Inodes count */
|
|
__le32 s_blocks_count; /* Blocks count */
|
|
__le32 s_r_blocks_count; /* Reserved blocks count */
|
|
__le32 s_free_blocks_count; /* Free blocks count */
|
|
__le32 s_free_inodes_count; /* Free inodes count */
|
|
__le32 s_first_data_block; /* First Data Block */
|
|
__le32 s_log_block_size; /* Block size */
|
|
__le32 s_log_frag_size; /* Fragment size */
|
|
__le32 s_blocks_per_group; /* # Blocks per group */
|
|
__le32 s_frags_per_group; /* # Fragments per group */
|
|
__le32 s_inodes_per_group; /* # Inodes per group */
|
|
__le32 s_mtime; /* Mount time */
|
|
__le32 s_wtime; /* Write time */
|
|
__le16 s_mnt_count; /* Mount count */
|
|
__le16 s_max_mnt_count; /* Maximal mount count */
|
|
__le16 s_magic; /* Magic signature */
|
|
__le16 s_state; /* File system state */
|
|
__le16 s_errors; /* Behaviour when detecting errors */
|
|
__le16 s_minor_rev_level; /* minor revision level */
|
|
__le32 s_lastcheck; /* time of last check */
|
|
__le32 s_checkinterval; /* max. time between checks */
|
|
__le32 s_creator_os; /* OS */
|
|
__le32 s_rev_level; /* Revision level */
|
|
__le16 s_def_resuid; /* Default uid for reserved blocks */
|
|
__le16 s_def_resgid; /* Default gid for reserved blocks */
|
|
/*
|
|
* These fields are for EXT2_DYNAMIC_REV superblocks only.
|
|
*
|
|
* Note: the difference between the compatible feature set and
|
|
* the incompatible feature set is that if there is a bit set
|
|
* in the incompatible feature set that the kernel doesn't
|
|
* know about, it should refuse to mount the filesystem.
|
|
*
|
|
* e2fsck's requirements are more strict; if it doesn't know
|
|
* about a feature in either the compatible or incompatible
|
|
* feature set, it must abort and not try to meddle with
|
|
* things it doesn't understand...
|
|
*/
|
|
__le32 s_first_ino; /* First non-reserved inode */
|
|
__le16 s_inode_size; /* size of inode structure */
|
|
__le16 s_block_group_nr; /* block group # of this superblock */
|
|
__le32 s_feature_compat; /* compatible feature set */
|
|
__le32 s_feature_incompat; /* incompatible feature set */
|
|
__le32 s_feature_ro_compat; /* readonly-compatible feature set */
|
|
__u8 s_uuid[16]; /* 128-bit uuid for volume */
|
|
char s_volume_name[16]; /* volume name */
|
|
char s_last_mounted[64]; /* directory where last mounted */
|
|
__le32 s_algorithm_usage_bitmap; /* For compression */
|
|
/*
|
|
* Performance hints. Directory preallocation should only
|
|
* happen if the EXT2_COMPAT_PREALLOC flag is on.
|
|
*/
|
|
__u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
|
|
__u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
|
|
__u16 s_padding1;
|
|
/*
|
|
* Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
|
|
*/
|
|
__u8 s_journal_uuid[16]; /* uuid of journal superblock */
|
|
__u32 s_journal_inum; /* inode number of journal file */
|
|
__u32 s_journal_dev; /* device number of journal file */
|
|
__u32 s_last_orphan; /* start of list of inodes to delete */
|
|
__u32 s_hash_seed[4]; /* HTREE hash seed */
|
|
__u8 s_def_hash_version; /* Default hash version to use */
|
|
__u8 s_reserved_char_pad;
|
|
__u16 s_reserved_word_pad;
|
|
__le32 s_default_mount_opts;
|
|
__le32 s_first_meta_bg; /* First metablock block group */
|
|
__u32 s_reserved[190]; /* Padding to the end of the block */
|
|
};
|
|
|
|
/*
|
|
* Codes for operating systems
|
|
*/
|
|
#define EXT2_OS_LINUX 0
|
|
#define EXT2_OS_HURD 1
|
|
#define EXT2_OS_MASIX 2
|
|
#define EXT2_OS_FREEBSD 3
|
|
#define EXT2_OS_LITES 4
|
|
|
|
/*
|
|
* Revision levels
|
|
*/
|
|
#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
|
|
#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
|
|
|
|
#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
|
|
#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
|
|
|
|
#define EXT2_GOOD_OLD_INODE_SIZE 128
|
|
|
|
/*
|
|
* Feature set definitions
|
|
*/
|
|
|
|
#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
|
|
( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
|
|
#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
|
|
( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
|
|
#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
|
|
( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
|
|
#define EXT2_SET_COMPAT_FEATURE(sb,mask) \
|
|
EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
|
|
#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask) \
|
|
EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
|
|
#define EXT2_SET_INCOMPAT_FEATURE(sb,mask) \
|
|
EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
|
|
#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask) \
|
|
EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
|
|
#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
|
|
EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
|
|
#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask) \
|
|
EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
|
|
|
|
#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
|
|
#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
|
|
#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
|
|
#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
|
|
#define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
|
|
#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
|
|
#define EXT2_FEATURE_COMPAT_ANY 0xffffffff
|
|
|
|
#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
|
|
#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
|
|
#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
|
|
#define EXT2_FEATURE_RO_COMPAT_ANY 0xffffffff
|
|
|
|
#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
|
|
#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
|
|
#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
|
|
#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
|
|
#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
|
|
#define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
|
|
|
|
#define EXT2_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
|
|
#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
|
|
EXT2_FEATURE_INCOMPAT_META_BG)
|
|
#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
|
|
EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
|
|
EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
|
|
#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED ~EXT2_FEATURE_RO_COMPAT_SUPP
|
|
#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED ~EXT2_FEATURE_INCOMPAT_SUPP
|
|
|
|
/*
|
|
* Default values for user and/or group using reserved blocks
|
|
*/
|
|
#define EXT2_DEF_RESUID 0
|
|
#define EXT2_DEF_RESGID 0
|
|
|
|
/*
|
|
* Default mount options
|
|
*/
|
|
#define EXT2_DEFM_DEBUG 0x0001
|
|
#define EXT2_DEFM_BSDGROUPS 0x0002
|
|
#define EXT2_DEFM_XATTR_USER 0x0004
|
|
#define EXT2_DEFM_ACL 0x0008
|
|
#define EXT2_DEFM_UID16 0x0010
|
|
/* Not used by ext2, but reserved for use by ext3 */
|
|
#define EXT3_DEFM_JMODE 0x0060
|
|
#define EXT3_DEFM_JMODE_DATA 0x0020
|
|
#define EXT3_DEFM_JMODE_ORDERED 0x0040
|
|
#define EXT3_DEFM_JMODE_WBACK 0x0060
|
|
|
|
/*
|
|
* Structure of a directory entry
|
|
*/
|
|
|
|
struct ext2_dir_entry {
|
|
__le32 inode; /* Inode number */
|
|
__le16 rec_len; /* Directory entry length */
|
|
__le16 name_len; /* Name length */
|
|
char name[]; /* File name, up to EXT2_NAME_LEN */
|
|
};
|
|
|
|
/*
|
|
* The new version of the directory entry. Since EXT2 structures are
|
|
* stored in intel byte order, and the name_len field could never be
|
|
* bigger than 255 chars, it's safe to reclaim the extra byte for the
|
|
* file_type field.
|
|
*/
|
|
struct ext2_dir_entry_2 {
|
|
__le32 inode; /* Inode number */
|
|
__le16 rec_len; /* Directory entry length */
|
|
__u8 name_len; /* Name length */
|
|
__u8 file_type;
|
|
char name[]; /* File name, up to EXT2_NAME_LEN */
|
|
};
|
|
|
|
/*
|
|
* Ext2 directory file types. Only the low 3 bits are used. The
|
|
* other bits are reserved for now.
|
|
*/
|
|
enum {
|
|
EXT2_FT_UNKNOWN = 0,
|
|
EXT2_FT_REG_FILE = 1,
|
|
EXT2_FT_DIR = 2,
|
|
EXT2_FT_CHRDEV = 3,
|
|
EXT2_FT_BLKDEV = 4,
|
|
EXT2_FT_FIFO = 5,
|
|
EXT2_FT_SOCK = 6,
|
|
EXT2_FT_SYMLINK = 7,
|
|
EXT2_FT_MAX
|
|
};
|
|
|
|
/*
|
|
* EXT2_DIR_PAD defines the directory entries boundaries
|
|
*
|
|
* NOTE: It must be a multiple of 4
|
|
*/
|
|
#define EXT2_DIR_PAD 4
|
|
#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
|
|
#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
|
|
~EXT2_DIR_ROUND)
|
|
#define EXT2_MAX_REC_LEN ((1<<16)-1)
|
|
|
|
static inline void verify_offsets(void)
|
|
{
|
|
#define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));
|
|
A(EXT2_SB_MAGIC_OFFSET, s_magic);
|
|
A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);
|
|
A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);
|
|
#undef A
|
|
}
|
|
|
|
/*
|
|
* ext2 mount options
|
|
*/
|
|
struct ext2_mount_options {
|
|
unsigned long s_mount_opt;
|
|
kuid_t s_resuid;
|
|
kgid_t s_resgid;
|
|
};
|
|
|
|
/*
|
|
* second extended file system inode data in memory
|
|
*/
|
|
struct ext2_inode_info {
|
|
__le32 i_data[15];
|
|
__u32 i_flags;
|
|
__u32 i_faddr;
|
|
__u8 i_frag_no;
|
|
__u8 i_frag_size;
|
|
__u16 i_state;
|
|
__u32 i_file_acl;
|
|
__u32 i_dir_acl;
|
|
__u32 i_dtime;
|
|
|
|
/*
|
|
* i_block_group is the number of the block group which contains
|
|
* this file's inode. Constant across the lifetime of the inode,
|
|
* it is used for making block allocation decisions - we try to
|
|
* place a file's data blocks near its inode block, and new inodes
|
|
* near to their parent directory's inode.
|
|
*/
|
|
__u32 i_block_group;
|
|
|
|
/* block reservation info */
|
|
struct ext2_block_alloc_info *i_block_alloc_info;
|
|
|
|
__u32 i_dir_start_lookup;
|
|
#ifdef CONFIG_EXT2_FS_XATTR
|
|
/*
|
|
* Extended attributes can be read independently of the main file
|
|
* data. Taking i_mutex even when reading would cause contention
|
|
* between readers of EAs and writers of regular file data, so
|
|
* instead we synchronize on xattr_sem when reading or changing
|
|
* EAs.
|
|
*/
|
|
struct rw_semaphore xattr_sem;
|
|
#endif
|
|
rwlock_t i_meta_lock;
|
|
#ifdef CONFIG_FS_DAX
|
|
struct rw_semaphore dax_sem;
|
|
#endif
|
|
|
|
/*
|
|
* truncate_mutex is for serialising ext2_truncate() against
|
|
* ext2_getblock(). It also protects the internals of the inode's
|
|
* reservation data structures: ext2_reserve_window and
|
|
* ext2_reserve_window_node.
|
|
*/
|
|
struct mutex truncate_mutex;
|
|
struct inode vfs_inode;
|
|
struct list_head i_orphan; /* unlinked but open inodes */
|
|
#ifdef CONFIG_QUOTA
|
|
struct dquot *i_dquot[MAXQUOTAS];
|
|
#endif
|
|
};
|
|
|
|
#ifdef CONFIG_FS_DAX
|
|
#define dax_sem_down_write(ext2_inode) down_write(&(ext2_inode)->dax_sem)
|
|
#define dax_sem_up_write(ext2_inode) up_write(&(ext2_inode)->dax_sem)
|
|
#else
|
|
#define dax_sem_down_write(ext2_inode)
|
|
#define dax_sem_up_write(ext2_inode)
|
|
#endif
|
|
|
|
/*
|
|
* Inode dynamic state flags
|
|
*/
|
|
#define EXT2_STATE_NEW 0x00000001 /* inode is newly created */
|
|
|
|
|
|
/*
|
|
* Function prototypes
|
|
*/
|
|
|
|
/*
|
|
* Ok, these declarations are also in <linux/kernel.h> but none of the
|
|
* ext2 source programs needs to include it so they are duplicated here.
|
|
*/
|
|
|
|
static inline struct ext2_inode_info *EXT2_I(struct inode *inode)
|
|
{
|
|
return container_of(inode, struct ext2_inode_info, vfs_inode);
|
|
}
|
|
|
|
/* balloc.c */
|
|
extern int ext2_bg_has_super(struct super_block *sb, int group);
|
|
extern unsigned long ext2_bg_num_gdb(struct super_block *sb, int group);
|
|
extern ext2_fsblk_t ext2_new_block(struct inode *, unsigned long, int *);
|
|
extern ext2_fsblk_t ext2_new_blocks(struct inode *, unsigned long,
|
|
unsigned long *, int *);
|
|
extern void ext2_free_blocks (struct inode *, unsigned long,
|
|
unsigned long);
|
|
extern unsigned long ext2_count_free_blocks (struct super_block *);
|
|
extern unsigned long ext2_count_dirs (struct super_block *);
|
|
extern void ext2_check_blocks_bitmap (struct super_block *);
|
|
extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
|
|
unsigned int block_group,
|
|
struct buffer_head ** bh);
|
|
extern void ext2_discard_reservation (struct inode *);
|
|
extern int ext2_should_retry_alloc(struct super_block *sb, int *retries);
|
|
extern void ext2_init_block_alloc_info(struct inode *);
|
|
extern void ext2_rsv_window_add(struct super_block *sb, struct ext2_reserve_window_node *rsv);
|
|
|
|
/* dir.c */
|
|
extern int ext2_add_link (struct dentry *, struct inode *);
|
|
extern ino_t ext2_inode_by_name(struct inode *, struct qstr *);
|
|
extern int ext2_make_empty(struct inode *, struct inode *);
|
|
extern struct ext2_dir_entry_2 * ext2_find_entry (struct inode *,struct qstr *, struct page **);
|
|
extern int ext2_delete_entry (struct ext2_dir_entry_2 *, struct page *);
|
|
extern int ext2_empty_dir (struct inode *);
|
|
extern struct ext2_dir_entry_2 * ext2_dotdot (struct inode *, struct page **);
|
|
extern void ext2_set_link(struct inode *, struct ext2_dir_entry_2 *, struct page *, struct inode *, int);
|
|
|
|
/* ialloc.c */
|
|
extern struct inode * ext2_new_inode (struct inode *, umode_t, const struct qstr *);
|
|
extern void ext2_free_inode (struct inode *);
|
|
extern unsigned long ext2_count_free_inodes (struct super_block *);
|
|
extern void ext2_check_inodes_bitmap (struct super_block *);
|
|
extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
|
|
|
|
/* inode.c */
|
|
extern struct inode *ext2_iget (struct super_block *, unsigned long);
|
|
extern int ext2_write_inode (struct inode *, struct writeback_control *);
|
|
extern void ext2_evict_inode(struct inode *);
|
|
extern int ext2_get_block(struct inode *, sector_t, struct buffer_head *, int);
|
|
extern int ext2_setattr (struct dentry *, struct iattr *);
|
|
extern void ext2_set_inode_flags(struct inode *inode);
|
|
extern void ext2_get_inode_flags(struct ext2_inode_info *);
|
|
extern int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
|
|
u64 start, u64 len);
|
|
|
|
/* ioctl.c */
|
|
extern long ext2_ioctl(struct file *, unsigned int, unsigned long);
|
|
extern long ext2_compat_ioctl(struct file *, unsigned int, unsigned long);
|
|
|
|
/* namei.c */
|
|
struct dentry *ext2_get_parent(struct dentry *child);
|
|
|
|
/* super.c */
|
|
extern __printf(3, 4)
|
|
void ext2_error(struct super_block *, const char *, const char *, ...);
|
|
extern __printf(3, 4)
|
|
void ext2_msg(struct super_block *, const char *, const char *, ...);
|
|
extern void ext2_update_dynamic_rev (struct super_block *sb);
|
|
extern void ext2_write_super (struct super_block *);
|
|
|
|
/*
|
|
* Inodes and files operations
|
|
*/
|
|
|
|
/* dir.c */
|
|
extern const struct file_operations ext2_dir_operations;
|
|
|
|
/* file.c */
|
|
extern int ext2_fsync(struct file *file, loff_t start, loff_t end,
|
|
int datasync);
|
|
extern const struct inode_operations ext2_file_inode_operations;
|
|
extern const struct file_operations ext2_file_operations;
|
|
|
|
/* inode.c */
|
|
extern const struct address_space_operations ext2_aops;
|
|
extern const struct address_space_operations ext2_nobh_aops;
|
|
|
|
/* namei.c */
|
|
extern const struct inode_operations ext2_dir_inode_operations;
|
|
extern const struct inode_operations ext2_special_inode_operations;
|
|
|
|
/* symlink.c */
|
|
extern const struct inode_operations ext2_fast_symlink_inode_operations;
|
|
extern const struct inode_operations ext2_symlink_inode_operations;
|
|
|
|
static inline ext2_fsblk_t
|
|
ext2_group_first_block_no(struct super_block *sb, unsigned long group_no)
|
|
{
|
|
return group_no * (ext2_fsblk_t)EXT2_BLOCKS_PER_GROUP(sb) +
|
|
le32_to_cpu(EXT2_SB(sb)->s_es->s_first_data_block);
|
|
}
|
|
|
|
#define ext2_set_bit __test_and_set_bit_le
|
|
#define ext2_clear_bit __test_and_clear_bit_le
|
|
#define ext2_test_bit test_bit_le
|
|
#define ext2_find_first_zero_bit find_first_zero_bit_le
|
|
#define ext2_find_next_zero_bit find_next_zero_bit_le
|